{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata. Fed continuously.","feed_url":"https://feed.craftedsignal.io/tags/cve-2026-18157/feed.json","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cpes":[],"_cs_cves":[{"cvss":7.8,"id":"CVE-2026-18157"}],"_cs_exploited":false,"_cs_has_poc":false,"_cs_poc_references":[],"_cs_products":["yggdrasil-worker-package-manager"],"_cs_severities":["high"],"_cs_tags":["privilege-escalation","linux","cve-2026-18157"],"_cs_type":"advisory","_cs_vendors":["yggdrasil"],"content_html":"\u003cp\u003eCVE-2026-18157 identifies a critical argument injection vulnerability within the yggdrasil-worker-package-manager's APT backend. The vulnerability stems from improper validation of package names passed to the underlying apt-get utility. A local attacker who has already gained low-privileged access to the system can provide a maliciously crafted package name - specifically one beginning with a hyphen - which the application fails to distinguish from legitimate command-line flags.\u003c/p\u003e\n\u003cp\u003eWhen processed, these injected strings are interpreted by apt-get as command-line options rather than arguments. By leveraging specific apt-get options that permit the execution of arbitrary scripts or custom configurations (such as pre- or post-installation hooks), an attacker can achieve code execution with root privileges. This vulnerability is significant as it provides a direct path from low-privileged system access to a full root-level compromise of the host's integrity, confidentiality, and availability.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eAttacker gains initial low-privileged access to the target host environment.\u003c/li\u003e\n\u003cli\u003eAttacker identifies that the system utilizes yggdrasil-worker-package-manager for automated package operations.\u003c/li\u003e\n\u003cli\u003eAttacker crafts a package name starting with a hyphen (e.g., \u0026quot;-oDir::Etc::SourceList=/tmp/malicious_list\u0026quot;).\u003c/li\u003e\n\u003cli\u003eAttacker triggers a package installation or update request via the vulnerable worker interface.\u003c/li\u003e\n\u003cli\u003eyggdrasil-worker-package-manager constructs an apt-get command string incorporating the malicious input without proper sanitization.\u003c/li\u003e\n\u003cli\u003eapt-get executes the command, interpreting the injected hyphenated string as a valid operational option.\u003c/li\u003e\n\u003cli\u003eapt-get hooks or configuration directives are manipulated to execute arbitrary commands.\u003c/li\u003e\n\u003cli\u003eAttacker achieves remote code execution or privilege escalation to the root user.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation of this vulnerability results in full system compromise. As the affected worker process interacts with the system's package manager, the resulting code execution occurs with root-level privileges. This enables an attacker to install persistent backdoors, exfiltrate sensitive data, manipulate system binaries, or disable security auditing mechanisms. The impact is categorized as high, with a CVSS v3.1 base score of 7.8, reflecting the potential for total system takeover by an authenticated local actor.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cp\u003ePrioritized actions for detection and mitigation:\u003c/p\u003e\n\u003cul\u003e\n\u003cli\u003ePatch or update yggdrasil-worker-package-manager to the version that includes sanitization for input passed to apt-get.\u003c/li\u003e\n\u003cli\u003eAudit logs for execution of apt-get processes with anomalous command-line flags that suggest option injection (e.g., usage of \u0026quot;-o\u0026quot; or \u0026quot;--option\u0026quot; flags that reference temp or user-controlled directories).\u003c/li\u003e\n\u003cli\u003eEnforce strict least-privilege policies for accounts authorized to trigger package manager operations via the yggdrasil worker.\u003c/li\u003e\n\u003cli\u003eMonitor for unexpected parent-child process relationships where the worker service spawns apt-get with non-standard command-line arguments.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-07-31T03:33:40Z","date_published":"2026-07-31T03:33:40Z","id":"https://feed.craftedsignal.io/briefs/2026-07-yggdrasil-apt-injection/","summary":"An argument injection vulnerability in the APT backend of yggdrasil-worker-package-manager allows local attackers to manipulate apt-get command-line arguments to achieve root-level code execution.","title":"Argument Injection Vulnerability in yggdrasil-worker-package-manager","url":"https://feed.craftedsignal.io/briefs/2026-07-yggdrasil-apt-injection/"}],"language":"en","title":"CraftedSignal Threat Feed - Cve-2026-18157","version":"https://jsonfeed.org/version/1.1"}